What outcome variables did the authors use to measure the effectiveness of the intervention?
Did the authors measure any mediating explanatory factors or theoretical variables? That is, did the authors measure any theoretical variables that were proposed to contribute to the problem, and which the intervention aimed to change?
Critical analysis – did the authors measure the outcome variable adequately? Were they able to draw firm conclusions about the intervention’s effectiveness?
Were they able to draw conclusions as to why the intervention was or was not effective?
What precipitating (triggers of the problem) and/or perpetuating factors (sustaining the problem) are addressed by the intervention?